Dapagliflozin Attenuates NLRP3/Caspase-1 Signaling Pathway-Mediated Pyroptosis of Vascular Smooth Muscle Cells by Down-regulating CTSB

Background: • Atherosclerosis is a chronic inflammatory disease.Pyroptosis triggers and amplifies the inflammatory response and plays an important role in AS.Cathepsin B (CTSB) canpromote AS and activate NLRP3 to mediate pyroptosis.Dapagliflozin (DAPA) can inhibit cell pyroptosis to improve AS.This study aimed to explore the effect of DAPA on oxidized low-density lipoprotein (ox-LDL)-induced pyroptosis of vascular smooth muscle cells (VSMCs)and its underlying mechanism. Methods • VSMCs were transfected with cathepsin B (CTSB)-overexpressing and -silencing lentiviral vectors.Then,VSMCs were treated with different concentrations of ox-LDL ( 0,50,100,150µg/ml ), Hoechst33342/PI double staining and LDH release assay were used to detect cell pyroptosis.After VSMCs were treated with different concentrations of DAPA ( 0.1µM, 1.0µM, 5.0µM, 10µM, 25µM, 50µM ), the proliferation activity of VSMCs was detected by CCK8 method.On the basis of ox-LDL-induced VSMCs pyroptosis, DAPA intervention, overexpression and silencing of CTSB were used to observe the effects of DAPA and CTSB on Ox-LDL-mediated VSMCs pyroptosis. Results • 1) VSMCs stably transfected with CTSB-overexpressing and -silencing lentiviruses were obtained, 150 µg/mL was the optimal concentration of ox-LDL for inducing pyroptosis of VSMCs, and 0.1 µM was the optimal concentration of DAPA for ameliorating pyroptosis of VSMCs. 2) Ox-LDL-induced pyroptosis of VSMCs was worsened by overexpression of CTSB but suppressed by silencing of CTSB. 3) DAPA attenuated ox-LDL-induced pyroptosis of VSMCs through down-regulating CTSB and NLRP3. 4) Overexpression of CTSB based on DAPA intervention aggravated ox-LDL-induced pyroptosis of VSMCs. Conclusion • DAPA attenuates NLRP3/caspase-1 pathway-mediated pyroptosis of VSMCs through down-regulating CTSB.